EM8504 Datasheet | EM Microelectronic

Description The EM8504 is an integrated power management solution for low power applications. It is specifically designed for efficient operation with Dye-Sensitized Solar Cells (DSSC) in the µW to m W range. To optimize harvesting efficiency, the EM8504 incorporates a maximum power point tracking (MPPT) controller based on a fixed Voltage at Maximum Power Point (VMPP). The device is designed to speed-up system start-up time when the main energy storage element (aka Long Term Storage - LTS) is pletely discharged or insufficiently charged to supply the application, by using a secondary energy storage element (Short Term Storage - STS). When using a non-rechargeable primary battery the EM8504's onboard PMU offers a mechanism to extend battery life when assisted by a harvesting element. The EM8504 incorporates a boost converter able to start with an input voltage as low as 300 m V and an input power of few μW. In functional mode the EM8504 operates at energy levels from a DC harvesting source as low as 100 m V and 1 μW. To maximize harvesting efficiency the EM8504 uses an external voltage to track the maximum power point. The EM8504 is capable of working with a variety of energy elements as secondary storage, namely re-chargeable batteries, supercapacitors or conventional capacitors. In all cases the EM8504 maintains its fast start-up capability that depends only on the harvester conditions and the STS capacitor value. The EM8504 integrates voltage supervisory functions. Minimum and maximum voltages are controlled on the LTS element to prevent damage to the energy storage element. Harvester minimum voltage monitoring allows stopping the DCDC limiting power loss when no energy can be harvested. Output voltages are kept in a safe range for the application. To perform granular power management of the application, the EM8504 integrates four independent supply outputs. It is possible to stop the DCDC converter by setting the pin HRV_DIS to higher than 2.3V. The EM8504 is...